1. Field of the Invention
The present invention relates, in general, to separating two immiscible fluids, such as oil and water, front each other, and in particular, to a device for accumulating oily runoff water from a surface such as a parking lot and passing a portion of that water to an immiscible fluids separator.
2. Information Disclosure Statement
Separators for separating immiscible fluids, such as oil and water, from each other are well-known. An example of such a separator is given in Greene et al., U.S. Pat. No. 5,266,191, issued Nov. 30, 1993, and assigned to the assignee of the present invention.
Some have attempted to use immiscible liquid separators to process runoff water from a surface, such as a parking lot or the roof of a building, in order to prevent the oils, etc., that have accumulated on that surface from passing into a municipality's sewage system or a nearby river and causing environmental damage. Such accumulation can happen as oils drip front cars onto the parking lot, or as oils drip from machinery on the roof of the building. When rainfall occurs, the initial runoff water from the surface washes the oil from the surface, and subsequent runoff water during the same storm is relatively clean. It is impractical to design and dedicate an immiscible liquids separator for the task of processing all of the vast quantity of runoff water that might flow from the surface during any expected possible rainfall, because such a separator would be huge and the enormous capacity that would be required of such a separator would only rarely be required during peak rainfall activity, whereas the volume of oily runoff water that truly would need to be processed is relatively small, appearing during the initial moments of the rainstorm.
It is therefore desirable to have an apparatus that allows the use of a smaller immiscible liquids separator than would be otherwise possible, that will direct the dirty initial runoff water to the separator, and that will bypass the separator and direct subsequent and relatively clean runoff water into a drain. Such a bypass should only occur when the rated flow capacity of the separator might be exceeded, and means should also be provided to ensure that the rated flow capacity of the separator is not, in fact, exceeded. Such a bypass should also only be of the subsequent and relatively clean runoff water, and not of the dirty initial runoff water.
A preliminary patentability search in Class 210, subclasses S 13, 519, 521, 532.1, 538, 539, 540, and 799, produced the following patents, some of which may be relevant to the present invention: Pike, U.S. Pat. No. 1,734,777, issued Nov. 5, 1929; Boosey, U.S. Pat. No. 2,071,160, issued Feb. 16, 1937; Marsh, U.S. Pat. No. 2,076,380, issued Apr. 6, 1937; Hirshstein, U.S. Pat. No. 2,284,737, issued Jun. 2, 1942; Boosey, U.S. Pat. No. 2,288,989, issued Jun. 26, 1941; Mathels, U.S. Pat. No. 2,479,386, issued Aug. 16, 1949; Johnson, U.S. Pat. No. 2,644,584, issued Jul. 7, 1953; LaLonde et al., U.S. Pat. No. 3,527,348, issued Sep. 8, 1970; Preus et al., U.S. Pat. No. 3,862,040, issued Jan. 21, 1975; Wolde-Michael, U.S. Pat. No. 4,422,931, issued Dec. 27, 1983; Cloud, U.S. Pat. No. 4,684,467, issued Aug. 4, 1987; Hall, U.S. Pat. No. 4,915,823, issued Apr. 10, 1990; Keep et al., U.S. Pat. No. 5,229,015, issued Jul. 20, 1993; Fink, U.S. Pat. No. 5,236,585, issued Aug. 17, 1993; and Steadman et al., U.S. Pat. No. 5,204,000, issued Apr. 20, 1993.